Improvement in machines for burnishing the heads of screws



3 Sheets-jSheet 1. A C. D. ROGERS. Machine for Burnishing the Heads of Screws, 850.

No. 217,024. Pan-mme 1uly1,1879.

wlTNEssEs. Y INVENTDR.

N. PETERSl PHUTQLITHOGRAFHER, WASHINGTON. D C.

. C. D. ROGERS. Machine fr B-urnishing thejI-Ieads of Screws., 8vo.

Patented July 1, 1.879.-

F'IE.2.

INVENTR.

WITNESEES. JX. y/7% N'PETERS. PHOTO-UTHOGRAPHER. WSHINQT'DR D. C.

3 Sheets-Sheet 3.

, D. ROGERS. Machine for Burnishing the Heads ofScreWs, 81:13.

JulryL 1879.

WrT'NEssEa NVF'LIES. PHBTLMLITHQQHAPHER, WASHINGTON. D C,

UNITED STATESPATENT @union CHARLES D. ROGERS, OF PROVIDENCE, RHODE ISLAND, ASSIGNOR TO THE AMERICAN SCREW COMPANY, OF SAME PLACE.

IMPROVEMENT IN MACHINES FR BURNISHING THE HEADS 0F SCREWS, dc.

Specification forming part of Letters Patent N 0.2172024, dated July l, 1879; application filed Marclr20, 1879.

To all whom it may concern.:

Beit known that I, CHARLES D. ROGERS, of the city and county of Providence, and

f State of Rhode Island, have invented a new and useful Improvement in Machines for Burnishing the Heads of Screws and similar articles; and I do hereby declare that the following specification, `taken in connection with the ing operation upon the entire surface of said heads.

Referring to the three sheets of drawings, Figure l represents a plan of my improved machine, with the hopper removed andthe spindle in section. Fig. 2 shows the machine in side elevation. Fig. Sirepresents an end view, with a portion of the frame cut away, the better to show the working parts; and Fig.

[4 shows a horizontal section of the feeding device, which conveys the screws to the spindle. As shown in Figs. 2 and 3, Arepresents the hopper, in Which` are placed the screws in mass vwhose heads are to be burnished. This hopper is supplied with mechanism in common use yfor selecting' the screws from the mass and delivering them to a conveyer, as at B, from Vwhich the said screws are supplied one by one to a roulette recipient, as at C. This recipient has upon its peripheryT a series of grooves, c, for receiving the screws, which are carried by intermittent partial revolutions of said recipient to a spoon-ieed, as at D, the screws being retained in the grooves until discharged therefrom by a semieircular guard-plate, as at E, Figs. 2 and 3.

The office of the spoon-feed D is to convey the .screws from the roulette C into axialalignment with a holding-spindle, as at F, in which they are seated and held by mechanisnrhereinafter described,

As the machine is organized the revolution of the recipient C is dependent upon the movements of the spoon-feed D, which is mounted upon an arm, as at F1, Figs. 2 and 4, pivoted to the frame. This arm is engaged by a bellcrank lever, F2, which is operated by .a cam, as at G, on the shaft G and a reactionary spring, as at g, to produce a laterally-reciprocating movement of the feed D. Upon the spindle which carries the roulette recipient C is also mounted a bell-crank lever, as at H, the short arm beingforked and the long arm carrying a pawl upon its end. During the movement of the feed D toward the recipient the forked arni of the lever H is acted upon by a projection, d, on said feed, causing the pawl to engage one of the grooves c and partially rotate the recipient C, thereby releasing a screw which falls into a receptacle in said feed and is conveyed into axial alignment with the spindle F. The receptacle in the feed D,

for receiving the screws, has sides formed by two separable hinged wings, d', controlled by 1 springs, as shown atrFig. 4, the inner surface of the free end of each Wing being rounded or beveled and furnished with a selnicircular y opening, to facilitate and allow of the outward vpassage of the screws.

For seating the screws in the spindle F, the feed D is supplied with a plunger, as at I,

Figs. land 4, the said plunger beingI in en-L gagement with an arm, as at J, Fig.- l, which has a longitudinal reciprocating movement imparted to it by a cam, as at K, and a spring, as at 7c. The action of the cam K causes the plunger to advance, its end coming in contact with the screw-head, and push the screw longitudinally out of the feed D and into the `spindle F, where it is griped directly under the head, and held against rotationupon its own axis.

As shown in Figs. l and 3, the griping-spindle Fis a split tube, secured within and to a tube, F3, which is mounted in a cylindrical casing, as at L, having bearings in the frame of the machine. The diameter of the rear portion of the tube F3 is reduced, producing a shoulder, as at f1, against which bears a spiral spring, m, the other end of said spring taking bearing on a sliding block, M, to which are pivoted toggle-levers, as at N. These levers N are inclosed in a cylindrical sliding sleeve, O, which is engaged by a forked arm, P, mounted on a stud, as at p, and controlled by a cam, as at Q, on the cam-shaft G. At the proper time the cam Q causes the arm 1 and sleeve O to advance and straighten the levers N, which action, through the block M and spring m, advances the tube F3 and produeesan engagement between the shoulders f on the spindle F and the conical end l of the casing L. The end of the spindle is thus closed upon the screw with sufficient force to hold it, as above specified. After the bur- :nishin g has been completed the screws are released by a backward movement of the spin; dle, 85e., and are expelled by a spring-plunger.

4 (Shown at f2, Fig. 1.)

The machine, as thus far described, is not essentially different from the organization of screw-machines heretofore employed, which have combinedA therewith dressing-tools for shaving or shaping the heads of screws. ,Therefore no claim is made to the feeding devices, griping-spindle, or its mechanism.

The distinctive dierence between the present machine and machines employing dressing-tools for shaving or shapin g the heads of screws consists in the employment, in the general organization described, of a tool for burnishing the heads, the action of which inthe combination is peculiar and distinctive from the action of the head-dressing tools in the machines referred to.

Referring to Figs. 1 and 3 of the drawings, R represents the burnisher, mounted on an axle in the forked end ofk a radius-arm, S, which arm is pivoted to a carriage, as at T, so as to be capablev of longitudinal and lateral movements on said carriage. The pivotal pin S1 passes through a slot in the carriage, and' is seated against acushionspring. (Shown at s1, Fig. 1.) Upon one side of the arm S is an inclined plane, s, Fig. 1, and when the burnisher R is not in contact with the head of a f screw the lateral position of the forward portion of the arm S relative to its carriage T is as shown in Fig. 1the foot of the inclined plane s bearing against a pin, as at t, by the force of a spring, s2, Fig. 8, which exerts pressure upon the arm S.

The burnisher R is brought into contact with a screw-head by the forward movement of the carriage T, which movement is caused by the engagement of a cam, U, Figs. 1 and 2, with a bell-crank lever, V. The vertical arm of this lever supports and is hinged to the forward end of the carriage T, the rear portion of said carriage being splined to a standard, T',

secured to the frame of the machine. The retreat of the burnisher after it has completed its work is accomplished by a spring, S2, Fig. 1, which, through an arm,'.s3, and link s4, Fig. 3, operates upon the lever V to move the carriage T and its burnisherv into their rearward position.

That a new portion of the surface of the burnisher `may be presented to each successive screw, the spindle upon which it is mounted.y is provided with a ratchet', W, which ratchetis engaged by a stationary hook, w, Fig. 1,. each time the burnisher moves forward, and it is thereby partially revolved.

The operation of those portions of the machine which act to convey the screws from thehopper to the holding-spindle and clamp thenr therein will be sufficiently understood from the foregoing description to need no further explanation; therefore I will proceed to show the operation of the burnishingtool.

A screw being clamped in the holding-spindle F, the cam U acts upon the bell-crank lever V, and produces a forward movement of the carriage T, arm S, and burnisher R, the

burnisher being partially turned upon its axis y during this movement by the engagement of the hook yw with the ratchet W. The forward movement of the carriage T brings the burnisher in contact, under a yielding pressure, with the edge of the screw-head, the axis of the arm S'being perpendicular to that of the screw; but further longitudinal advancement is prevented, owing to the relative position of these axes until the said burnisher is laterally moved. This is accomplished by the engagement of the pin t upon the moving carriage with the inclined plane s on the arm S. This pin, during the continued advancement of the carriage T, moves over the inclined plane s, and causes a lateral movement of the burnisher until it has arrived at such a portion of the screw-head that the contour of said head will alone serve to complete the lateral movement.

During the remaining portion of the forward movement of the burnisher, and during such portion of the retreat as is necessary to bring it back to the position specified, the contour of the screw-head wholly governs the lateral movements of the burnisher, the longitudinal vmovements being produced by the cam U and spring S2, and the burnisher being held up to yits work by the spring s2.

It will be seen from the foregoing that the burnishing-tool is capable of yielding to enable it to conform its path of movement to the particular shape of the half-round or other formed head to be burnished, and that the head itself `performs an office in giving direction to the path of movement of the tool; whereas in machines employing dressing-tools for shaving or shaping the heads of screws or similar articles the tool has a positive movement given to it, which is unaffected by the particular shape of the head operated upon. Again, the feature of construction which provides for making the burnishing-tool intermittingly revoluble upon its axis upon each backward and forward movement of the carriage upon which it is mounted, is important in machines which may give a positive movementto the burnisher and dispense with the means which in my organization enables it to yieldto the particular shape of the head.

Having described my invention, what I claim, and desire to secure by Letters Patent, 1s-

1. rlhe combinatiolrof a revolving spindle capable of holding a screw or other article the head of which is to be burnished and a burnishing-tool held to its Work by spring-press ure and moved by suitable means in the plane ofthe longitudinal axis of the revolving spindle, said burnishing-tool having a horizontallylateral movement given to it as it advances,

vmodified by the shape of the head to be burnished, substantially as described.

2. The combination, substantially as specii fied, offa revolving spindle capable of holding a screw or other article the head f which is to be burnished, a burnishing-tool which has the proper movements given to it by suitable mechanism, described, for enabling it to exert pressure upon such head, and a pawl and ratchet or equivalent means for intermittin gly revolving the burnisher to present afresh section of its surface to each successive head, as

set forth.

3. The combination of a revolving spindle and a yielding burnisher mounted upon a radius-arm pivoted to a carriage, which has a movement given to it in a direction radial to the axis of the revolving spindle by suitable mechanism, as described, the said radius-arm, as it is advanced by the carriage, receiving a horizontally-lateral movement by means as described, to enable the burnisher to conform to the shape of the head to be burnished, substantially as specified.

cHAnLns DI ROGERS.

Witnesses: i

J oHN D. THURsToN, 4I. KNIGHT. 

